1. Field of the Invention
The present invention relates to computer peripheral input devices, and more particularly to a computer peripheral input system with different input modules.
2. Description of the Prior Art
Driven both by the needs of users and the capabilities of various implementation technologies, computers and the way that people interact with them are redesigned again and again.
To make computer systems easier for people to use, various systems have included stylus-type input devices (typically used with a digitizer tablet). Because of their similarity to conventional writing implements, stylus-type devices are particularly well suited to be used for character input, among pointing devices, in addition to functioning as a pointing device. When used, stylus-type input devices have generally been provided in addition to a keyboard.
Keyboards, whether used for personal computers, calculators or toys, usually have a plurality of keys, which are arranged in a row-column matrix. Depression, or actuation, of a key within this matrix results the completion of a circuit, which connects one row to one column. Thus, the matrix can be scanned by feeding digital “1” (5 volts in TTL Logic) to every column and reading the output from the rows.
Drawing tablets, while long known in the computer field, have just recently become increasingly prevalent. A drawing tablet can be defined as a device comprised of an electromagnetic sensitive writing surface on which a person can position a hand-held stylus, and the position where the stylus touches is measured in two dimensions (x and y). The measured position is converted into an electrical digital code (i.e. encoded) in a conventional manner. The stylus may be a pen or any narrow object or instrument like a mouse, puck.
A kind of computer input device being able to provide input signals of a keyboard and a digitizer tablet has been developed. This prior computer input device is provided with a character code detection loop and a conducting trace detection loop within a keyboard device. Thus, the keyboard device can provide character code data and X-Y coordinate data to the computer, and improving graphic and handwriting functions of the computer. In this prior computer input device, two micro-controllers are employed to respectively process the character code input data and the X-Y coordinate input data received from the keyboard device, and then sending the character code data and the X-Y coordinate data, respectively through a keyboard communication interface and a digitizer tablet communication interface to the computer for further processing.
This prior computer input device utilizes two micro-controllers and two communication interfaces for respectively processing/communicating character codes and coordinate data. It is not economically effective whether in manufacturing technique or production cost. Accordingly, it is an intention to provide an improved computer input device, which not only increases functions of the computer but also more satisfies economic effectiveness.